Aircraft wake turbulence is an inherent outcome of aircraft flight,presenting a substan-tial challenge to air traffic control,aviation safety and operational efficiency.Building upon data obtained from coherent Dopple...Aircraft wake turbulence is an inherent outcome of aircraft flight,presenting a substan-tial challenge to air traffic control,aviation safety and operational efficiency.Building upon data obtained from coherent Doppler Lidar detection,and combining Dynamic Bayesian Networks(DBN)with Genetic Algorithm-optimized Backpropagation Neural Networks(GA-BPNN),this paper proposes a model for the inversion of wake vortex parameters.During the wake vortex flow field simulation analysis,the wind and turbulent environment were initially superimposed onto the simulated wake velocity field.Subsequently,Lidar-detected echoes of the velocity field are simulated to obtain a data set similar to the actual situation for model training.In the case study validation,real measured data underwent preprocessing and were then input into the established model.This allowed us to construct the wake vortex characteristic parameter inversion model.The final results demonstrated that our model achieved parameter inversion with only minor errors.In a practical example,our model in this paper significantly reduced the mean square error of the inverted velocity field when compared to the traditional algorithm.This study holds significant promise for real-time monitoring of wake vortices at airports,and is proved a crucial step in developing wake vortex interval standards.展开更多
Compared with non-gray model,equivalent gray model has equal calculation accuracy but much higher computing speed.To solve the existing problems of the equivalent gray method,sole ternary model was developed.In the mo...Compared with non-gray model,equivalent gray model has equal calculation accuracy but much higher computing speed.To solve the existing problems of the equivalent gray method,sole ternary model was developed.In the model,coupling solving process of energy balance equations is omitted and the model zone is real closed.Meanwhile,the full furnace temperature and heat flow calculations are avoided,which makes it easier to find the relationship between the equivalent gray gas radiation characteristic parameter and the initial conditions.The radiation characteristic parameter was calculated with different temperature combinations,different model zone sizes and different partial pressures of absorbent gas.The results show the similar variations in the absorption coefficient and emissivity for the equivalent gray model,which both decrease with the increase of the gas temperature and the surface temperature（especially the former one）as well as the model zone size while increase with the increase of the partial pressure of absorbent gas.展开更多
基金supported by the National Natural Science Foundation of China (No.U2133210).
文摘Aircraft wake turbulence is an inherent outcome of aircraft flight,presenting a substan-tial challenge to air traffic control,aviation safety and operational efficiency.Building upon data obtained from coherent Doppler Lidar detection,and combining Dynamic Bayesian Networks(DBN)with Genetic Algorithm-optimized Backpropagation Neural Networks(GA-BPNN),this paper proposes a model for the inversion of wake vortex parameters.During the wake vortex flow field simulation analysis,the wind and turbulent environment were initially superimposed onto the simulated wake velocity field.Subsequently,Lidar-detected echoes of the velocity field are simulated to obtain a data set similar to the actual situation for model training.In the case study validation,real measured data underwent preprocessing and were then input into the established model.This allowed us to construct the wake vortex characteristic parameter inversion model.The final results demonstrated that our model achieved parameter inversion with only minor errors.In a practical example,our model in this paper significantly reduced the mean square error of the inverted velocity field when compared to the traditional algorithm.This study holds significant promise for real-time monitoring of wake vortices at airports,and is proved a crucial step in developing wake vortex interval standards.
基金Sponsored by National Science and Technology Support Plan of China(2011AA060104)
文摘Compared with non-gray model,equivalent gray model has equal calculation accuracy but much higher computing speed.To solve the existing problems of the equivalent gray method,sole ternary model was developed.In the model,coupling solving process of energy balance equations is omitted and the model zone is real closed.Meanwhile,the full furnace temperature and heat flow calculations are avoided,which makes it easier to find the relationship between the equivalent gray gas radiation characteristic parameter and the initial conditions.The radiation characteristic parameter was calculated with different temperature combinations,different model zone sizes and different partial pressures of absorbent gas.The results show the similar variations in the absorption coefficient and emissivity for the equivalent gray model,which both decrease with the increase of the gas temperature and the surface temperature（especially the former one）as well as the model zone size while increase with the increase of the partial pressure of absorbent gas.
